WASHINGTON, April 6 (Reuters) - The United States imposed sanctions on Friday against Russian businessmen, companies and officials, striking at associates of President Vladimir Putin in one of Washington's most aggressive moves to punish Moscow for what it called a range of "malign activity," including alleged meddling in the 2016 U.S. election.

The action, taken under pressure from the U.S. Congress, freezes the U.S. assets of "oligarchs" such as aluminum tycoon Oleg Deripaska and lawmaker Suleiman Kerimov, whose family controls Russia's largest gold producer, Polyus.

The Treasury Department sanctions on seven Russian oligarchs and 12 companies they own or control, plus 17 senior Russian government officials, are likely to complicate U.S. President Donald Trump's hopes for good relations with Putin.

"The Russian government operates for the disproportionate benefit of oligarchs and government elites, Treasury Secretary Steve Mnuchin said in a statement.

He said Moscow "engages in a range of malign activity around the globe, including continuing to occupy Crimea and instigate violence in eastern Ukraine, supplying the Assad regime with material and weaponry as they bomb their own civilians, attempting to subvert Western democracies, and malicious cyber activities."

Russian lawmaker Konstantin Kosachev, chairman of the international affairs committee of Russia's upper house of parliament, said the sanctions were baseless and unfriendly, Interfax news agency reported.

The sanctions could potentially hurt the Russian economy, especially the financial and energy sectors, and are part of Washington's effort to hold Russia to account for allegedly interfering in the election, which Moscow denies.

Shares in aluminum producer Rusal were down 2.2 percent on Moscow's exchange after the company was named on the sanctions list.

Russian state companies under the U.S. sanctions will receive additional government support, Interfax cited Russia's Industry and Trade Minister Denis Manturov as saying.

U.S. intelligence agencies say Russia used hacking and propaganda in an effort eventually aimed at favoring Trump over Democrat Hillary Clinton.

Special Counsel Robert Mueller is investigating whether Trump's campaign colluded with Russia in the 2016 election, something that Trump denies. Mueller has indicted 13 Russians and three organizations in his probe.

SLOW ACTION ON RUSSIA

Trump has faced fierce criticism - including from fellow Republicans - for doing too little to punish Russia for the election meddling, aggression in Ukraine, and support of President Bashar al-Assad in Syria's civil war.

He angered many members of Congress by failing for months to implement sanctions on Russia that lawmakers passed nearly unanimously last year.

But pressure for Washington to take action against Russia has been mounting in a series of disputes reminiscent of Cold War tensions.

Putin's government has been blamed for the poisoning of a former Russian double agent living in Britain last month and the United States and several European states announced plans to expel more than 100 Russian diplomats in response.

In February, the White House blamed Russia for the international "NotPetya" cyber attack, which has been called the most destructive and costly in history.

On March 15, the Trump administration said it would impose sanctions on 19 people and five entities, including Russian intelligence services, for cyber attacks stretching back at least two years.

Friday's sanctions were authorized by the Countering America's Adversaries Through Sanctions Act, known as CAATSA, which Trump reluctantly signed into law in August.

Under the law, the U.S. Treasury Department released a public list of 210 people, including 96 wealthy Russian businessmen close to Putin's government and network, who could be subject to future sanctions.

The oligarchs were not immediately sanctioned then but the existence of the list - and a more detailed classified annex - created uncertainty over international business dealings with some Russian sectors.

Chris Painter, the former top cyber diplomat at the U.S. State Department, said the latest sanctions are unlikely to deter the Kremlin unless Trump formally condemns Putin.

Painter, who left government last year, criticized Trump's rhetoric toward Putin including a congratulatory call last month when Putin won another presidential term in a widely criticized election.

"We need the head of our country saying, 'This is not going to happen,'" Painter said. "Thats a critical piece." (Reporting by Lesley Wroughton and Patricia Zengerle Additionatl reporting by Doina Chiacu, Tim Ahmann and Susan Heavey Writing by Alistair Bell Editing by Yara Bayoumy and Bill Trott)